Abstract Despite advances in dialysis, only 50% of dialysis patients are alive 3 years after the onset of end-stage renal disease (ESRD). Although withdrawal of dialysis precedes 1 in 4 deaths of patients with ESRD, withdrawal from dialysis and aggressive treatment is rarely discussed by patients and their surrogates with sufficient time to consider alternatives such as hospice or dying at home. Over the last decade, we have developed and iteratively tested SPIRIT (Sharing Patient's Illness Representation to Increase Trust), a patient and family- centered advance care planning intervention based on the Representational Approach to Patient Education. We have established feasibility, patient-surrogate acceptability, and efficacy. SPIRIT is a 6-step, 2-session, face-to-face intervention to promote cognitive and emotional preparation for end-of-life decision making for patients with ESRD and their surrogates. In these explanatory trials carried out in dialysis clinics, SPIRIT was delivered by trained research nurses. Patients and surrogates in SPIRIT showed significant improvement in preparedness for end-of-life decision making, and surrogates in SPIRIT reported significantly improved post- bereavement psychological outcomes after the patient's death compared to a no treatment comparison condition. The logical, critical next step is to ask: Will SPIRIT be effective as part of routine care in real-world settings with less control? To address this very issue, we will conduct a real-world effectiveness- implementation study. We propose a multicenter, clinic-level cluster randomized trial to evaluate the effectiveness of SPIRIT delivered by dialysis care providers as part of routine care in free-standing outpatient dialysis clinics compared to usual care plus delayed SPIRIT implementation. Simultaneously, we will evaluate the implementation of SPIRIT, including sustainability. We will recruit 400 dyads of patients at high risk of death in the next year and their surrogates from 30 dialysis clinics in 4 states to accomplish the following aims: Aim 1. Examine the effectiveness of SPIRIT compared to usual care on preparedness outcomes for end-of-life decision making (defined as dyad congruence on goals of care, patient decisional conflict, and surrogate decision-making confidence) at 2 weeks post-intervention; Aim 2. Evaluate the process outcomes of SPIRIT implementation: acceptability, fidelity, intervention costs, and sustainability during the initial and delayed implementation of SPIRIT; Aim 3. Examine the effectiveness of SPIRIT and usual care on surrogates' post- bereavement distress (anxiety, depression, and post-traumatic distress symptoms) at 3 months after the patient's death; and Aim 4. Secondary Aim: Examine the effectiveness of SPIRIT and usual care on end-of- life treatment intensity (percentages of patients hospitalized, having ICU admission, and having intensive procedures and length of hospital stay) during the final month of life. This real-world trial of SPIRIT will generate novel, meaningful insights that can push the frontiers of knowledge in improving ACP in dialysis care.